The present invention is related to a method and a system for taking over data and a device for processing data which continues a process by taking over a takeover data of a current system processing unit to a spare system processing unit, when there is some trouble with the current system processing unit.
Up to the present, there has been some cases that a trouble occurs due to some causes in the current system computer while the computer is processing a data. In such case, the spare system computer will store the takeover data in a memory, when the current system computer transmits the processed transferring data through the network to the spare system computer. Namely, the current system computer takes over the takeover data to the spare system computer. Then the spare system computer resumes the process in accordance with the takeover data stored in the memory.
Some other systems store the takeover data in such nonvolatile memory as a memory attached to a battery backup, a disk and a tape. The nonvolatile memory will not destroy the stored takeover data even if a power supply within the computer is cut off. For this reason, the takeover data can be taken over through the nonvolatile memory.
The volatile memory destroys a stored takeover data when the power supply is cut off. For this reason, the volatile memory is not used for takeover data. Besides, it sometimes happens that the computer is reset or reactivated by the errors which occur in the core part of a memory, a central processing unit (CPU) and an operating system. Also in this case, volatile memory cannot be used for the takeover data.
A high-speed nonvolatile memory like the memory attached to the battery backup is expensive. For this reason, the expensive memory attached to the battery backup has not been used for general computers, but the disk and the tape have been used. Otherwise, the takeover data has been transmitted to the spare system computer to be stored in the memory.
However, both a data transferring speed of the disk and the magnetic tape and the data transferring speed to the spare system computer have been slow. The takeover data has been stored in a nonvolatile area of the disk one by one, whenever the takeover data was changed or added. For this reason, there has been a problem that it takes a lot of time to process the takeover data and the data processing ability is lowered.